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Agglutination (biology)
Encyclopedia
Agglutination is the clumping of particles. The word agglutination comes from the Latin agglutinare, meaning "to glue."
This occurs in biology in three main examples:
4. Also occurs when people are given blood transfusions of the wrong blood group.
Hemagglutination
is when the particles involved are red blood cell
s. The agglutin is called hemagglutinin
.
In cross-matching
, agglutination occurring when donor red blood cells and recipient's serum or plasma are incubated together indicates that the donor blood is incompatible
for that particular recipient.
s.
An example is the PH-L form of phytohaemagglutinin
.
(1853–1927), discovered specific agglutination in 1896. The clumping became known as Gruber-Durham reaction. Gruber introduced the term agglutinin (from the Latin) for any substance that caused agglutination of cells.
French physician Fernand Widal (1862–1929) put Gruber and Durham's discovery to practical use later in 1896, using the reaction as the basis for a test for typhoid fever
. Widal found that blood serum from a typhoid carrier caused a culture of typhoid bacteria to clump, whereas serum from a typhoid-free person did not. This Widal test
was the first example of serum diagnosis.
Austrian physician Karl Landsteiner
found another important practical application of the agglutination reaction in 1900. Landsteiner's agglutination tests and his discovery of ABO blood groups was the start of the science of blood transfusion
and serology
which had made transfusion possible and safe after a while.
This occurs in biology in three main examples:
- The clumping of cells such as bacteria or red blood cells in the presence of an antibody. The antibody or other molecule binds multiple particles and joins them, creating a large complex.
- The coalescing of small particles that are suspended in a solution; these larger masses are then (usually) precipitated.
- An allergic reaction type occurrence where cells become more compacted together to prevent foreign materials entering them. This is usually the result of an antigen in the vicinity of the cells.
4. Also occurs when people are given blood transfusions of the wrong blood group.
Hemagglutination
Hemagglutination
Hemagglutination, or haemagglutination, is a specific form of agglutination that involves red blood cells . It has two common uses in the laboratory: blood typing and the quantification of virus dilutions.-Blood Typing:...
is when the particles involved are red blood cell
Red blood cell
Red blood cells are the most common type of blood cell and the vertebrate organism's principal means of delivering oxygen to the body tissues via the blood flow through the circulatory system...
s. The agglutin is called hemagglutinin
Hemagglutinin
Influenza hemagglutinin or haemagglutinin is a type of hemagglutinin found on the surface of the influenza viruses. It is an antigenic glycoprotein. It is responsible for binding the virus to the cell that is being infected...
.
In cross-matching
Cross-matching
Cross-matching blood, in transfusion medicine, refers to the complex testing that is performed prior to a blood transfusion, to determine if the donor's blood is compatible with the blood of an intended recipient, or to identify matches for organ transplants. Cross-matching is usually performed...
, agglutination occurring when donor red blood cells and recipient's serum or plasma are incubated together indicates that the donor blood is incompatible
Blood type
A blood type is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells . These antigens may be proteins, carbohydrates, glycoproteins, or glycolipids, depending on the blood group system...
for that particular recipient.
Leukoagglutination
Leukoagglutination is when the particles involved are white blood cellWhite blood cell
White blood cells, or leukocytes , are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a...
s.
An example is the PH-L form of phytohaemagglutinin
Phytohaemagglutinin
Phytohaemagglutinin is a lectin found in plants, especially legumes. PHA actually consists of two closely related proteins, called leucoagglutinin and PHA-E. The letters E and L indicate these proteins agglutinate Erythrocytes and Leukocytes...
.
Agglutination in microbiology
Agglutination is commonly used as a method of identifying specific bacterial antigens, and in turn, the identity of such bacteria. Because the clumping reaction occurs quickly and is easy to produce, agglutination is an important technique in diagnosis.History of discoveries
Two bacteriologists, Herbert Edward Durham (-1945) and Max von GruberMax von Gruber
Max von Gruber was an Austrian scientist.As a bacteriologist he discovered specific agglutination in 1896 with his colleague Herbert Edward Durham...
(1853–1927), discovered specific agglutination in 1896. The clumping became known as Gruber-Durham reaction. Gruber introduced the term agglutinin (from the Latin) for any substance that caused agglutination of cells.
French physician Fernand Widal (1862–1929) put Gruber and Durham's discovery to practical use later in 1896, using the reaction as the basis for a test for typhoid fever
Typhoid fever
Typhoid fever, also known as Typhoid, is a common worldwide bacterial disease, transmitted by the ingestion of food or water contaminated with the feces of an infected person, which contain the bacterium Salmonella enterica, serovar Typhi...
. Widal found that blood serum from a typhoid carrier caused a culture of typhoid bacteria to clump, whereas serum from a typhoid-free person did not. This Widal test
Widal test
Test whereby bacteria causing typhoid fever are mixed with serum containing specific antibodies obtained from an infected individual. It is a presumptive serological test for enteric fever or undulant fever. In case of Salmonella infections, it is a demonstration of the presence of O-soma...
was the first example of serum diagnosis.
Austrian physician Karl Landsteiner
Karl Landsteiner
Karl Landsteiner , was an Austrian-born American biologist and physician of Jewish origin. He is noted for having first distinguished the main blood groups in 1900, having developed the modern system of classification of blood groups from his identification of the presence of agglutinins in the...
found another important practical application of the agglutination reaction in 1900. Landsteiner's agglutination tests and his discovery of ABO blood groups was the start of the science of blood transfusion
Blood transfusion
Blood transfusion is the process of receiving blood products into one's circulation intravenously. Transfusions are used in a variety of medical conditions to replace lost components of the blood...
and serology
Serology
Serology is the scientific study of blood serum and other bodily fluids. In practice, the term usually refers to the diagnostic identification of antibodies in the serum...
which had made transfusion possible and safe after a while.
See also
- MacrophageMacrophageMacrophages are cells produced by the differentiation of monocytes in tissues. Human macrophages are about in diameter. Monocytes and macrophages are phagocytes. Macrophages function in both non-specific defense as well as help initiate specific defense mechanisms of vertebrate animals...
- Immune SystemImmune systemAn immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...
- Blocking antibody
- Mannan Oligosaccharides (MOS)